MESOSCALE PRECIPITATION DISCUSSION 0725
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
617 PM EST WED DEC 30 2015
 
AREAS AFFECTED......SOUTHEAST TO LOWER MID ATLANTIC... 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 302306Z - 310306Z
 
SUMMARY...DESPITE WEAKENING RAINFALL RATES... ADDITIONAL FLASH
FLOODING WILL BE POSSIBLE THIS EVENING OVER SATURATED SOILS.

DISCUSSION...THE ONGOING HEAVY RAINFALL EVENT HAS PEAKED LATE THIS
AFTERNOON...PER THE WARMING/LOWERING CLOUD TOPS AND DIMINISHING
RADAR ESTIMATED RAINFALL RATE AS OF 22Z. HOWEVER...THE CONTINUED
FRONTOGENETIC SUPPORT SOUTH OF THE UPPER JET AXIS AND ALONG A
SURFACE BOUNDARY...ALONG WITH FAVORABLE THERMODYNAMIC PARAMETERS
AND SATURATED SOILS WILL LEAD TO THE POTENTIAL FOR ADDITIONAL
FLASH FLOODING WITHIN THE HEAVIER RAIN CORES.

DESPITE THE DECREASE IN DEEP LAYER INSTABILITY...MUCAPES BETWEEN
500-1000 J/KG ALONG WITH THE HIGHLY-ANOMALOUS PRECIPITABLE WATER
VALUES AROUND 1.75 INCHES WILL BE SUFFICIENT TO SUPPORT 3-HOURLY
RAINFALL RATES BETWEEN 1-2 INCHES...AS SUPPORTED BY THE 21Z HRRR
AND EXPERIMENTAL HRRR GUIDANCE. GIVEN THE RECENT HEAVY RAINS AND
LOWERING FFG...WITH CURRENT 3-HOURLY FFG VALUES BELOW 1.5 INCHES
OVER A LARGE PORTION OF THE OUTLOOK AREA...ADDITIONAL SHORT TERM
RUNOFF PROBLEMS MAY LINGER THIS EVENING.

HURLEY

ATTN...WFO...CAE...FFC...GSP...ILM...MHX...RAH...RNK...

ATTN...RFC...SERFC...

LAT...LON   36307790 35557782 34437954 33098174 32108364 
            32318490 33008509 33708440 34638286 35678110 
            36277915